Following positive lecanemab data in Alzheimer's, Eisai plans regulatory program

Japanese drugmaker Eisai’s (TYO: 4523) shares gained more than 17% to 6,784 yen today, after it released top-line results from the Clarity AD Phase III clinical trial for lecanemab, an investigational anti-amyloid beta (Aβ) protofibril antibody for the potential treatment of early Alzheimer’s disease.

The results show the drug was able to slow the rate of decline in people’s memory and thinking as well as function over 18 months, and also helped people with day-to-day activities.

Lecanemab met the primary endpoint (CDR-SB: Clinical Dementia Rating-Sum of Boxes) and all key secondary endpoints with highly statistically-significant results. Eisai will discuss this data with regulatory authorities in the USA, Japan and Europe with the aim to file for traditional approval in the USA and for marketing authorization applications in Japan and Europe by the end of Eisai's fiscal year 2022, which ends March 31, 2023.